1. Field of the Invention
The present invention relates to a greenhouse structure. In particular, the present invention relates to a novel solar-energy type, photovoltaic greenhouse structure.
2. Description of the Prior Art
A greenhouse is useful against typhoons, acid rain and insect pests, as well as in lowering temperature in summertime and keeping temperature high enough in wintertime. Because a greenhouse can provide plants or crops with suitable environment to grow, it is often used to culture plants or crops of high economic value, such as orchids or melons.
As well known by persons of ordinary skills in the art, greenhouse engineering resides in selecting suitable covering materials to control the micro-climate inside the greenhouse in accordance with the biological requirements of the plants and with the local climate along with various control equipments installed inside the greenhouse to keep the plants or crops in their best conditions to grow.
In order to keep the inner temperature within a suitable range, a greenhouse is usually designed to be equipped with a ventilation apparatus to ventilate excess heat during hot summer days and to raise the temperature by heaters during the harsh, cold winter days which are disadvantageous for the plants and crops.
However, in certain extreme conditions, even in the presence of a ventilation apparatus, such as a ventilator, it is still very hard to keep the greenhouse within an ideal temperature condition. Accordingly, additional and expensive air conditioning is needed. Such air conditioning is costly and consumes a lot of energy.
Besides, in order to control the light intensity inside the greenhouse, a greenhouse is often shaded. Excess UV light may do damage to both the physiological and biological functions of plants, such as burned leaves. At the same time, a shaded greenhouse keeps harmful UV light out as well so plants inside the greenhouse may grow in a much more favorable condition.
However, the traditional way to shade a greenhouse can neither filtrate sunlight of a specific wavelength effectively nor control the light intensity or a pre-selected light band of sunlight effectively. In addition the traditional way to shade a greenhouse also blocks the sunlight, IR for example, which facilitates the growth of plants, or photosynthesis.
Given the above, the current greenhouse structure still needs further improving and advancing.